The present invention relates to an advanced intelligent telephone network utilizing a peripheral platform to connect to multiple Service Control Points to perform various functions related to providing subscribers an array of telephone services.
Acronyms
The written description uses a large number of acronyms to refer to various services and system components. Although generally known, use of several of these acronyms is not strictly standardized in the art. For purposes of this discussion, acronyms therefore will be defined as follows:
Advanced Intelligent Network (AIN)
Central Office (CO)
Common Channel Inter-office Signaling (CCIS)
Common Language Location Identifier (CLLI)
Call Processing Record (CPR)
Data and Reporting System (DRS)
Integrated Service Control Point (ISCP)
Integrated Services Digital Network (ISDN)
Intelligent Peripheral (IP)
Local Area Network (LAN)
Multi-Services Application Platform (MSAP)
Service Control Point (SCP)
Service Creation Environment (SCE)
Service Logic Program (SLP)
Service Management System (SMS)
Service Node (SN)
Service Switching Point (SSP)
Signaling Transfer Point (STP)
Simplified Message Desk Interface (SMDI)
Transaction Capabilities Applications Part (TCAP)
Transmission Control Protocol/Internet Protocol
(TCP/IP)
While the advanced intelligent network (AIN) concept continues to evolve, it has now matured to the point where AIN networks are widely used. AIN networks provide network operators with considerable flexibility and economy in structuring their product offerings and providing their customers with numerous telephone conveniences and services. As a result, telephony services have become markedly sophisticated.
With AIN, many of the xe2x80x9cintelligentxe2x80x9d call processing functions can be off loaded from the generic switches to peripheral or adjunct computer systems (e.g., service control point), thereby reducing the switches"" processing burdens. The service control points (SCPs) assist the switches with the routing of calls and by providing data to implement customized calling features. The SCP is essentially a central control for the intelligent network. Because of the criticality of the SCP""s role, the SCP sites can be implemented in mated pairs in which two identical SCPs are xe2x80x9cpaired.xe2x80x9d Each SCP in the pair stores a duplicate copy of the subscribers"" call processing data, for the customers serviced through the particular pair of SCPs. In effect, if one SCP site fails, the mate continues to provide the same service to the subscribers.
In an AIN network, the SCPs rely on peripheral platforms to provide auxiliary call processing capabilities when instructed to do so. In general terms, a peripheral platform supports the execution of service logic programs or application processes. Specifically, peripheral platforms handle key functions such as announcements and digit collection. The use of peripheral platforms negates the need for switched based announcements, which have a number of serious drawbacks. One drawback involves incurring enormous expense in having to upgrade all telephone switching offices when more announcement capacity is required. Another disadvantage is the need to rely on a single switch vendor for such upgrades. Also, any service specific announcements must be loaded onto each switch providing the particular AIN service. Loading new announcements on large numbers of switching systems is time consuming and may require the services of expert personnel provided only by the switch equipment vendor.
The use of peripheral platforms are thus desirable because these drawbacks are eliminated. They provide readily adaptable means to add and change announcements to an AIN, without direct addition of equipment in each central office switching system. The platforms also serve to centralize announcement capabilities to some extent, so that announcement reprogramming does not always require reprogramming of equipment for every single switch through which an enhanced service is offered. Also, such platforms are easier to upgrade to add call processing capabilities, such as speech recognition and speaker identification.
In a typical network incorporating a peripheral platform, a signaling communication system for two-way communications of data messages interconnects a number of central office switching systems and connects the central office switching systems to the services control point. A separate signaling communication system provides two-way data signaling communications between the peripheral platform and multiple service control points. That is, the later signaling communication system is separate from the first signaling communication system, the central office switching systems, and the trunk circuits interconnecting the central office switching systems. The second signaling communication system also permits exchange of messages between the peripheral platforms, if more than one are present.
An AIN network may also include a plurality of peripheral platformsxe2x80x94or in more advanced networks, intelligent peripherals (IPs). One peripheral platform may connect to one switching system or to a number of the switching systems. Each such peripheral platform provides one or more auxiliary call processing capabilities in response to instructions from the SCP.
The typical AIN architecture allows the switched transport network to interact with database systems such as SCPs and peripheral platform such as IPs for obtaining information, data and support operations. This occurs when the switching network is triggered to access the database or peripheral by some condition that arises during processing of a telephone call.
IPs and similar platforms have become integral components in the AIN architecture in the delivery of advanced features and services. U.S. Pat. No. 5,572,583 to Wheeler discloses an IP offering one or more auxiliary call processing features in response to instructions from the SCP. The IP provides such enhanced call processing functions as announcement and digit collection, voice recognition, facsimile mail, and voice mail. U.S. Pat. No. 5,469,500 to Satter et al. discloses a processor for use in a telephone network, both as an IP controlled by a SCP and as a service node (SN) operating autonomously. The call processor includes a service creation environment (SCE) and stores call processing instructions in service logic tables for use by the service logic executive to handle and route calls.
Current AIN configurations assign one IP to a SCP. The SCPs control the intelligent peripherals in a master-slave relationship. The SCPs delegate various call processing tasks to their assigned IPs. Because of this one-to-one mapping of SCP to IP, the complexity with respect to operations and management of the AIN network significantly increases as more SCPs are added. In essence, the AIN network does not scale well under this scenario. Other inefficiencies result as well. A typical IP implementation involves the use of several minicomputers, networking and internetworking equipment which are expensive. Also, underutilized IPs are expensive from a maintenance and support perspective.
Futhermore, there is no readily viable method to provide regionalized services because of the single SCP to single IP mapping. For example, if a subscriber has traveled out of region, she would incur toll charges to access her service through interaction with an IP operating in her home region. As a consequence of the inflexibility of the IP/SCP configuration, the AIN network is inefficient.
Therefore, a need exists to better utilize IPs in the AIN. The configuration of the IP should promote optimal use of costly network resources. The configuration should more efficiently allot resources of an IP to multiple SCPs. In addition to providing economic savings, the modified network should also facilitate regionalized services and accommodate local calling scenarios where possible. By creating a regionalized approach, the out of region traveler in the previous example would be able to access her service via a local IP.
The present invention meets the above noted needs by providing a peripheral platform (e.g., IP) with the capability to handle data connections to multiple service control points. The peripheral platform is connected to one or more switching systems to provide call processing functions. The terms network ports and network interfaces, herein, are used synonymously to refer to physical and logical components necessary to achieve data communication, for example, to enable communications with an SCP. In other words, the invention pertains to the selection of network interface addresses that map to physical network ports and/or logical network ports. The peripheral platform has this functionality to select one SCP among multiple SCPs, and to select a port or interface on the SCP, using an algorithm (e.g., round-robin scheme) that distributes the data traffic loads from the peripheral platform among the network ports of the SCPs"" call processors.
Essentially, the processor in the peripheral platform queries a database (SCP Locator Database) which contains data records of SCP selection data to ultimately retrieve a network interface address, such as an Internet Protocol address, associated with the selected SCP. The SCP selection data may include data records of telephone digits related to the telephone stations, codes related to identification of the SCPs, and network addresses of the SCP network interfaces. The SCP Locator Database preferably resides within the peripheral platform but may reside in an SCP. Once the processor of the peripheral platform obtains a SCP network interface address, the processor establishes a data connection between the peripheral platform""s data communication interface and the SCP network interface.
In one implementation of the invention, a plurality of SCPs are grouped (called a xe2x80x9cSCP Matedxe2x80x9d group) in which a condition for the grouping is that each of the SCPs, in the group, has identical functionalities to any other service control point within the mated SCP group. If the group comprises two SCPs, it is termed a SCP Mated Pair. The algorithm implemented by the IP, selects one such mated group for a particular call, and selects a port on one of the SCPs of the group. The IP varies the port selection on different communication sessions to the mated group, to balance the load on the SCPs within the group.
The present invention is advantageous in that it provides the ability to select a particular SCP among multiple SCPs; and thus, permits consolidation of services controlled by multiple SCPs onto one peripheral platform.
Another advantage of the-invention is the capability to distribute the call processing load among multiple ports in a SCP site.
A further advantage arises from the reduction of hardware and software components required to implement an AIN with peripheral platforms.
Yet another advantage is the ability to situate peripheral platforms within the AIN to effect a more centralized topology, thereby achieving a regionalized approach to providing subscriber services and features.
In addition, the present invention has the advantage of permitting local calling scenarios when a subscriber, who is out of region, desires to access her services, without long distance routing to an intelligent peripheral.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.